


Small Eternities

by xylodemon



Category: Supernatural
Genre: Established Relationship, Future Fic, Hunting Husbands, M/M
Language: English
Status: Completed
Published: 2015-11-22
Updated: 2015-11-22
Packaged: 2018-05-02 23:04:08
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,201
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5267228
Author URL: https://archiveofourown.org/users/xylodemon/pseuds/xylodemon
Summary: <blockquote class="userstuff">
              <p>It's so fucking good. It's <i>always</i> fucking good.</p>
            </blockquote>





	Small Eternities

**Author's Note:**

  * For [peridium](https://archiveofourown.org/users/peridium/gifts).



> For Mara, on the occasion of her birthday.
> 
> [Also available on tumblr](http://xylodemon.tumblr.com/post/133756458214/deancas-fic-small-eternities-32k-nsfw).

On the morning of his forty-third birthday, Dean wakes up to Cas biting a slow, wet kiss on the inside of his thigh, lips and tongue and a soft scrape of teeth. He just lies there for a few moments, blinking the sleep out of his eyes and flexing his toes into the scratchy motel sheets. He breathes out Cas' name. Cas shifts closer, nosing at the crease of Dean's hip before sucking another mark into Dean's skin. His cheek brushes Dean's hardening dick; Dean gasps and pushes his hand into Cas' hair.

"Morning."

Cas turns his head. He says, "Happy Birthday," in a voice like rock-salt, then pins both hands at Dean's hips and swallows Dean down.

Arching up, Dean chokes out a noise. He digs his heel into Cas' thigh and claws at the sheets. Cas sucks him in and in and in, bobbing down until his nose is buried in the wiry curls at the base of Dean's dick, until his throat is fluttering and catching around the head, hot and slick and tight. Heat pools in Dean's gut dangerously fast; he's still only half-awake, and he never needs much where Cas is concerned, even after all these years. He keeps his hand in Cas' hair because he knows Cas likes it there, and he cradles Cas' face with the other so he can feel the stretch of Cas' lips and the pull of Cas' jaw, so he can feel the shape of himself when Cas' hollows his cheeks.

It's so fucking good. It's _always_ fucking good. Cas slides a hand over Dean's belly, softer now that Dean's on the wrong side of forty; before Dean can squirm away, he scratches his nails through the sparse trail under Dean's navel, then wraps his hand around Dean's dick. He pulls up to tease Dean's slit with the tip of his tongue, and Dean whines behind his teeth, his hips hitching up as he tries to chase the velvet-wet heat of Cas' mouth. 

"Jesus, Cas -- fuck."

Cas sucks a finger into his mouth, humming a little as his flushed-red lips bow around it. Then he leans back down, nudging in until Dean's leg is hooked over his shoulder. He mouths at the base of Dean's dick, his chin a stubble-rasp against Dean's balls, then drags a slow kiss up the length of it. He rubs a wet knuckle over Dean's hole as he swallows Dean down again, and Dean comes and comes and comes, his thighs shaking and his breath stuttering around a moan.

"Cas," Dean mumbles, his blood rushing in his ears. "God."

The bed creaks as Cas leans up on his elbow. A deep blush is burning down his jaw and throat, into his chest. Dean stares at him for a second -- at the dark glint in his eyes, at the filthy-slick shine around his mouth -- then grabs his arm and pulls him up. He straddles Dean's hips, sitting up on his knees as he wraps his hand around his dick. He's gorgeous like this, his head tipped back to show the long line of this throat. Dean runs his hands up the perfect curves of his thighs, then catches him by the hips and tugs him closer.

"C'mon. Get up here."

"Dean," Cas says, his back arching as he thrusts into his hand. "What do you want?"

"You." Heat crowds up under Dean's jaw; six years and he still can't always find the words. "I -- get up here."

Cas shifts up the bed until he's straddling Dean's chest. Moaning, he pushes his hand into Dean's hair and fucks into his fist three or four more times. The lamp on the nightstand flickers and pops, and then Cas is coming, warm and thick. The first pulse hits Dean's cheek; the second and third stripe his lips and chin. Want jolts through Dean like lightning, sparking fever-bright under his skin. His dick aches as it desperately tries to fill again. Hands shaking, he pulls Cas down against him, wrapping his arms around Cas' shoulders. Cas breathes into the hollow of Dean's throat for a few moments, then leans up to kiss the mess off Dean's face.

Eventually, Dean sighs and asks, "What time is it?"

"Almost seven-thirty. You said you wanted to get an early start." 

"Yeah, we probably should."

Cas mojos them clean, but Dean takes a shower anyway; he has a twinge in his shoulders from last night's eight-hour drive, and he needs to clear the sex-cobwebs out of his brain. When he gets out, the smell of coffee is warming the cigarette-stale air in the room. Dean pours himself a cup after he throws on his fed suit. He drinks it in the motel's dinky kitchen, sipping it slowly as he waits for Cas to get dressed. Cas doesn't take long; he lays his suit out on the bed and then suddenly he's wearing it. It's a hazy, gun-metal gray that makes his eyes look unreal.

"You want me to drop you off?" Dean asks, even though he knows the answer.

A smile tugs Cas' mouth. He can fly again now that heaven is (more or less) back to normal, so he does it every chance he gets. "No. I'll meet you back here when I'm finished with the witnesses." He kisses Dean goodbye before blipping out with a sound like the wind. 

Dean finishes his coffee, then rinses his mug in the dingy sink and heads out to the Impala. The Cerro Gordo county seat is six blocks from the motel, and Dean drives it at fifteen miles-per-hour because the roads are patched with ice. He parks in the only empty slot in front of the courthouse, and he feeds the meter two dollars in nickels and dimes, hoarding the quarters in case they're still on the road in a week and need to make a laundromat run. It's a cold morning, the air still knife-sharp from last night's snowfall. The snow has been shoveled into two neat piles that line the sidewalk.

His first stop is the sheriff's office. After a half-hour wait in the frostbitten lobby, a cadet with red hair and a beak nose informs him that the sheriff is out in the field. After another half-hour wait -- this time in a stuffy -- overheated conference room, he gets shunted to the deputy: a stout, Asian woman who points him to a chair before he can make his introductions.

"You here about the bank robbery down in Clarion?" she asks.

"No, ma'am. I wanted to talk to you about Mark Wilson."

She stares at him for a second, her eyebrows inching toward her hairline. "Mark Wilson? What would the feds want with a mugging?"

"We're just looking into a few things. His circumstances are similar to cases in two other states."

"You thinking serial killer?"

"No," Dean says carefully. The last thing he needs is the locals getting jumpy. "We're not thinking anything just yet. We're just... seeing where things lead."

She hesitates briefly, then leans back in her chair and says, "Wilson was attacked in the alley behind the Cavalier Club."

"Bar?"

"Yes, it's a bar. And not our fanciest establishment, if you follow me." When Dean nods, she continues, "The garbage truck found him in the morning. Multiple stab wounds. His watch and wallet were gone."

"You said multiple stab wounds. Did he have one --" Dean taps the side of his head " -- right about here?"

"Yes," she says. After a short pause, she mutters, "Serial killer," under her breath, then frowns at Dean and asks, "I suppose you'll want his file."

"Yes, ma'am."

"All right," she says, jerking her thumb toward her office door. The gold lettering on the inset window is faded in some places and peeling in others. "Dylan will get you everything you need."

Dylan turns out to be the same red-haired cadet from earlier; he has long, Ichabod Crane fingers, and he taps them impatiently on the counter as Dean fills out the file request with all his fake information. The photocopy job is another half-hour wait; Dean paces it out in the freezing-cold lobby because that's better than sweating through his coat. Once he has the file, he whips his collar up and walks across the street to the county morgue.

"Wilson?" the coroner barks. He has ruddy, alcoholic cheeks and the kind of mouth that's happiest chewing on a cigar. "Mark Wilson? He was boxed and buried weeks ago."

Dean offers him a smile. "I don't need to see the body. Just a copy of your report."

That takes another twenty minutes, which Dean spends making smalltalk with the coroner's office assistant and drinking the third-worst cup of coffee he's had all week. It's colder in the morgue than it is outside; a tremor is building in Dean's shoulders by the time he leaves. As he's walking to the car, he flips to the grainy copies of the post mortem photos. The only serious stab wounds is the one to the side of the head. The rest are superficial, like someone had shanked Wilson a few extra times just to make it look like there'd been a scuffle.

Back at the motel, Dean finds Cas sitting at the kitchen table, nursing a beer as he reads through his notes. He's out of his suit, dressed now in jeans and an old t-shirt and a blue button-down with the sleeves rolled up to his elbows. He looks up as Dean closes the door, his mouth curving with a smile. Dean drops the files on the table, then kisses his mouth and his jaw and the side of his neck.

"Kitsune?" Cas asks, tipping his head back as Dean nips at the spot below his ear. 

"Yeah. Same as the others." Dean kisses Cas' jaw again, then straightens up and starts shrugging out of his suit. "One money-shot to the side of the head. Everything else was just scratches."

"And the pituitary gland?" 

"Missing."

Cas considers this for a moment, then says, "Indianola, Altoona, and now Mason City. What does that tell us?"

"Squat. 'Cept that this fucker's moving north." Dean tosses his suit jacket over one of the chairs and starts unbuttoning his shirt. "I'll call Donna later and give her a heads-up. You know, in case this thing hits the state line before we can gank it." Sighing, Dean toes off his shoes. "Witnesses give you anything?"

"Wilson went to the Cavalier Club with his girlfriend and two other acquaintances. After several drinks, he had an argument with the girlfriend and went out the bar's back door, presumably to smoke a cigarette. They didn't see him again."

"And they didn't go looking for him?"

"After an hour or so, the girlfriend assumed he'd left in anger and did the same. When she left, the other two went to a different bar up the street."

"Great. That means nobody saw anything."

"No one ever does," Cas says mildly. His chair squeaks as he reaches for his beer. "Your brother called earlier."

"Yeah? He and Jody get that djinn wrapped up?"

"They killed it last night."

Dean tugs on a pair of jeans and digs around in his bag for a shirt. "Cool. Is he headed to us?"

"No," Cas says, quirking an eyebrow. "He's decided to stay in Sioux Falls a few more days."

Dean snorts out a laugh. "Yeah, I'll bet." Jody is living alone again; about three years ago, Claire and Alex got married and moved out and started hunting together on their own hook. Jody called Sam the next time she needed back-up, and Sam has been periodically driving out to Sioux Falls ever since. Dean hasn't exactly asked and Sam hasn't exactly offered, but -- hell. Math was never Dean's best subject, but those are some pretty easy numbers to add. "It'll be another week before they come up for air."

"Dean."

Dean just laughs again. Then he walks over to Cas and nudges in to stand between his legs. His t-shirt is still in his hand. Cas leans into him a little, tucking his face against Dean's chest and sliding his hands up to Dean's hips. They stand there for a few minutes, quiet as the motel's soundtrack loops around them. The heater kicks on with a hum, and a telephone rings upstairs, and a car's tires squeal in the parking lot, and Cas breathes against Dean's skin. 

"C'mon," Dean says finally, palming the curve of Cas' neck. "Help me figure out where this asshole's gonna feed next."

"Okay." 

Dean starts to pull away, stroking his hand through Cas' hair as he goes, pausing when he sees the flecks of gray at Cas' temples. It's just a few strands, barely visible in the motel room's shitty light. Dean ruffles them with shaky fingers.

"You feeling okay?"

"Of course. I don't get sick."

"No, I mean your mojo."

"Yes, Dean," Cas says. There's a sigh in his voice; this isn't the first time Dean has asked. Cas hasn't been back to heaven in years, and Dean worries sometimes that one day they'll remember he's slumming it with a human and cut him off out of spite. "My grace is fine. Why do you ask?"

"Nothing. I just -- you're going gray."

Cas looks up at him. "So are you."

Dean has been for a couple years now, has frost at his temples and salt in the day-old scruff he keeps because Cas likes the way it feels. "Yeah, but that's -- I'm human. You guys don't get old."

"Our vessels will age if we allow it."

"And you -- why?"

"Because you are."

Warmth blooms in Dean's chest, so startling and bright that all he can do is just stand there and try to breathe through it. His heart feels like it's beating in his throat.

"I know humans can be insecure about growing older," Cas says, standing and kissing the corner of Dean's mouth. "I thought it might comfort you if we did it together, but if it bothers you, I --"

"No," Dean says, kissing him, sucking his lower lip a little before he pulls away. "It doesn't bother me. I just -- God."

Carving out this new, almost-normal life together hasn't always been easy. Cas nearly got dragged back to heaven once, and Dean panicked a handful of times in the first two years, unused to having something permanent in his life and terrified by how much he loved Cas, by how deep his feelings ran once he finally stopped ignoring them. It's good now -- _they're_ good -- but some days Cas' immortality hovers around their edges in a way Dean can feel. He's going to die one day, and --

"Yes, you will," Cas says, his mouth moving against Dean's jaw. Dean huffs quietly; he hadn't realized he'd said that out loud. "I intend to delay it as long as possible, but you will."

A chill crawls up the back of Dean's neck. "And then what? You --"

"And then you'll go to heaven. And so will I."

"What --? Like, together?"

"Of course together. Unless --" An uncertain looks crosses Cas' face "-- unless that's not what you want. You --"

Dean kisses him again; _of course_ that's what he wants. He nips at Cas' lips until Cas opens up and lets him in, then curls his hand into Cas' hair and sucks Cas' tongue into his mouth. He isn't trying to start anything, not really, but Cas makes a quiet, inspiring noise and pulls Dean closer. Dean feels a quick flutter around him, the gunshot-like tension that means Cas is about to rip a hole in the air, and then they're tangled on the bed, the frame creaking in complaint from their sudden weight. The headboard rattles against the wall.

Cas doesn't zap off their clothes; undressing Dean the human way is something Cas really likes. He likes to skim his fingers around the waistband of Dean's jeans, and he likes to slowly thumb open the button. He likes to tease Dean's dick with his knuckles as he's tugging on the zipper, and he likes to run his hands down Dean's thighs as he's pulling his jeans off. Dean tries to return the favor, but he can't stop himself from touching Cas' dick. He wraps his hand around it as soon as Cas' fly is open, and he strokes Cas hard and slow, heat coursing under his skin when Cas moans his name, when Cas' hips snap and roll, when he starts fucking into Dean's fist.

"God, look at you," Dean says, because Cas is gorgeous, broad shoulders and a strong chest and a long, long throat. "You gonna come all over me again?"

"Dean," Cas says, his eyes dark. He fucks into Dean's hand a few more times, then sits up enough to get rid of his jeans. He leans over Dean as he's tossing them on the floor; this puts his chest right in Dean's face, so Dean sucks a nipple into his mouth, working it with his tongue and teeth until precome is beading from Cas' slit, hot and slick. 

When Cas straightens again he has the lube in his hand, and -- fuck. _Yes_. He starts to roll over -- he loves seeing Cas' face, but he also loves it when Cas fucks him from behind, loves it when Cas splits him open and fills him up while pinning him to the bed, holding him down -- but Cas sits back in his lap as he's spreading the lube on his fingers, and then he reaches behind himself and -- oh. _Oh_.

Cas hisses out a noise, his hips jerking and his back bowing, and Dean touches him everywhere, everywhere. He rakes his nails down Cas' sides and wrings his hands at Cas' waist, and he strokes his thumbs into the creases of Cas' hips. He runs his hands up the curves of Cas' thighs, then wraps one around Cas' dick and dips the other between Cas' legs. He palms Cas' balls, then nudges a finger inside Cas, right alongside the two Cas is already riding. Cas clutches around him, everything hot and tight and slick. His thighs start to shake. He heaves out a breath that sounds like Dean's name.

"Let me fuck you," Dean says. _Begs_. They've shared a bed for six years, and Dean still can't get enough of him. Dean gets hard sometimes just from thinking about him. "Cas, please."

Cas sinks down onto Dean's slow, so fucking slow. Dean is clawing at the sheets by the time Cas bottoms out, biting the inside of his cheek so he doesn't thrust up and come. Cas' mouth falls open around a moan, so Dean tugs him down for a kiss. His dick presses into Dean's belly, fever-hot and come-sticky. When he finally starts to move, Dean bites the corner of his jaw and sucks a mark into the hollow of his throat. He cards his fingers into the hair at Cas' temple, where Cas is letting himself go gray just for him.

"Harder," Cas whispers, rolling his hips filthy and slow. "I want to feel you."

Christ. Dean can't believe he gets to do this _forever_.


End file.
